Plate and Shell type welded plate heat exchangers are previously known, which are composed of a plate pack formed by heat exchange plates and a shell surrounding it, functioning as a pressure vessel. The core of the heat exchanger is usually formed by a plate pack composed of circular heat exchange plates having openings, where the plates are welded tightly together at openings therein and/or at the perimeters of the plates. A primary circuit of the heat exchanger is formed between the openings in the plates into the plate pack and a secondary circuit between connections of the shell surrounding the plate pack, so that a primary side flow medium flows in every other plate space and a secondary side flow medium in every other plate space. In this type of heat exchangers the flow connections on the pack side are usually placed in the ends of, the heat exchanger and the flow connections on the shell side in the shell, whereby the pipe structures of the heat exchanger easily become complicated and expensive with regards to construction costs.
In some applications of the heat exchanger it is advantageous to place all connections in the end. Such a structure is presented for example in patent publication WO2004/090450, where the shell side flows are led to run via the end with separate Z components or corresponding arrangements arranged between the end plate of the plate pack and the end plate of the heat exchanger. Separate flow guides however make the structure of the heat exchanger more complicated and thus also make the manufacture of the heat exchangers more complicated.